When I first saw a Jennings RJ-1, and
compared it to the open frame relay my
'220 was using, it was astonishing.
That was because vacuum relays are
good for isolation.
However RJ-1's are virtually useless
for a decent QRO rig above 20 meters
and that's because the RF ampacity
diminishes so rapidly with frequency
On bigger tube rigs it was necessary to
graduate to an RJ-2, but remember, those
vacuum relays only carry 12 amps at 32MHz.
So then there's the Jennings RF-10C.
The problem with getting vacuum relays with
enough contact gusto is they slow down because
of mass and inertia. The RF-10C is not too good
at 50WPM as you can imagine.
So it's a toss-up: You get a relay capable of
high speed QSK and it has poor ampacity and
blows out frequently, or you get an elevator
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